Inhaltsangabe: Abstract: Conventional workflow management focuses on improving the efficiency of business processes within one organization. However, processes should not only be supported within the enterprise, but also when crossing organizational boundaries, e.g. in order to support new forms of collaborations as virtual enterprises. Due to the different nature of interorganizational workflows, conventional workflow technology cannot be directly applied. The most important requirement specific to interorganizational workflow systems is obviously that they are able to deal with heterogeneity and that it is not too expensive to achieve interoperability. Also maintaining the privacy of internal processes is a major concern, and security issues should be addressed. This diploma thesis gives an introduction to conventional and interorganizational workflow management, their aspects and concepts. It elaborates the requirements relevant for interorganizational workflow systems, describes the most important approaches, projects, and initiatives that currently exist in the area of interorganizational workflows, including XML-based approaches, the standards of the WfMC, electronic marketplaces and electronic contracting. An evaluation of these approaches based on criteria derived from the requirements and other characteristics shows the differing strengths and weaknesses. The XML-based approaches provide standards for the process interfaces, and can cope with heterogeneous environments very well. Some of them even allow spontaneous commerce with new trading partners without custom integration. Traditional EDI is in principle similar, but has many disadvantages. The standards of the WfMC enable integration with a very low effort, if they are followed by software providers. But privacy and security are potential problem areas and the models of interoperability that realistically can be supported are simple. Electronic marketplaces and electronic contracting are ideal, if a